谁能帮我在登录表单上方显示错误的用户名和密码？？它不应该重定向到其他页面，而是必须显示在登录表单的正上方 我的代码包含
<!Doctype html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="mainpagestyle.css">
</head>
<style>
body {
background:#99ffff;
height:100%;
width:100%;
}
#footer {
poition:absolute;
padding: 1em;
color: white;
background-color: black;
clear: left;
text-align: center;
width: 100%;
border: 1px solid gray;
bottom : 0;
margin-top:90%;
}
</style>
<body>
<div class="container">
<h1>"MARK"</h1>
<ul id="headline" class="fallingtextrotator" style="height:2em">
<div class="grad"></div>
<form action="checkuser-pass.php" method="POST">
<div class="header">
<div>LOG<span>IN</span> </div>
</div>
</br>
<div class="login">
User Name: <input type="text" name="username"><br>
Password:    <input type="password" name="password"><br><br>
<input type="submit" name="submit" value="Login!">
        <a href=" ">FORGOT PASSWORD</a></div>
</div>
</br>
</form>
<ul id="headline" class="fallingtextrotator" style="height:2em">
<div class="grad"></div>
<form action="checkguest.php" method="POST">
<div class="headerr">
<div>SIGN<span>UP</span> </div>
</div>
</BR>
<div class="signup">
User Name: <input type="text" name="username"><br><br>
Email Id:    <input type="email" name="emailid"><br>
Password:    <input type="password" name="password"><br><br>
<input type="submit" name="submit" value="signup!">
</form>
</div>
</section>
<section class="footer">
<h5> © Navya Chowdary</h5>
<p><a href="#">Carrers </a>     <a href="#"> Blog</a>  
   <a href="#">Bussiness</a>
     <a href="#"> About Us</a>     <a
href="#">Suggestions or Complaints</a>      <a href="#">Bug</a>
</section>
</body>
</html>
这是我的 checkuser-pass.php
<?php
session_start();
$host="127.0.0.1";
$username="root";
$password="";
$db="markconnect";
$tb="userform";
$mysqli = new mysqli($host,$username,$password,$db) or die(mysqli_error());;
//DEFINE USERNAME AND PASSWORD
$username=$_POST['username'];
$password=$_POST['password'];
//echo md5($password); exit;
// To protect MySQL injection
$username = stripslashes($username);
$password = stripslashes($password);
$username = mysqli_real_escape_string($mysqli,$username);
$password = mysqli_real_escape_string($mysqli,$password);
$password = md5($password);
//echo $password; exit;
$sql="SELECT * FROM $tb WHERE username='$username' and password='$password'";
//echo $sql; exit;
$result=mysqli_query($mysqli,$sql);
//43 Mysql_num_row is counting table row
$count=mysqli_num_rows($result);
//print_r($count);
if($count==1){
$_SESSION['username'] = $username;
//include 'saver.php';
header("Location: saver.php");
}
else {
echo "Wrong Username or Password";
// <p>Please enter both username and password.</p>
}
ob_end_flush();
?>
最佳答案
如果您希望带有登录表单的页面处理请求，您必须将 checkuser-pass.php 中的 PHP 代码放入您的表单页面并:
<form action="" method="POST">
然后回显“用户名或密码错误”；可以通过单页表单处理轻松完成。
onepageformproccesing.php:
<?php
if(isset($_POST['submit'])){
echo $_POST['username'];
//process the form
//make the database query and check the password
//if user does not confirm make the error variable
$error = "Username or Password not correct!";
}
?>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Form Proccessing</title>
</head>
<body>
<?php if(isset($error)) { ?>
<div class="error">
<?php echo $error; ?>
</div>
<?php } ?>
<form method="post" action="">
Username: <input type="text" name="username"><br>
Password: <input type="password" name="password"><br>
<input type="submit" name="submit" value="Go!">
</form>
</body>
</html>
另一种方法是通过 Ajax 请求 checkuser-pass.php
其他方法是使用两页表单处理，但从 checkuser-pass.php 重定向回表单页面并使用 session 变量处理错误。
关于javascript - 如何在登录表单上方显示错误的用户名和密码？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/39436382/